Conventional bagmaking machines of horizontal or vertical construction have a fixed working stroke. The sealing means which produce the transverse seam may either be heat-sealers, for treatment of heat-sealable films, or welders for treatment of thermoplastic films. These conventional sealing stations have hitherto been driven either pneumatically, hydraulically, or mechanically by cams. These drive techniques result in a predetermined, unchangeable stroke, The clearance of the article lying on the conveyor belt is determined by the maximum height of the product to be processed or the maximum depth of the bag to be made.
There is, however, a need to be able to treat both large and small packages on the same machine, depending on the particular weight or bag size desired. This is made more difficult by the requirement that the packages must be provided with a transverse seam during their movement along a conveyor belt.